It’s a consumer’s worst nightmare: The Equifax data breach — perhaps already the scariest cybersecurity breach in history — was worse than the public knew.

Just this week, it was revealed that another 2.4 million Americans were impacted by the 2017 data breach. Attackers stole their names and part of their driver’s license numbers.

Last month, we learned that hackers accessed more information than Equifax previously disclosed to the public, according to The Wall Street Journal and CNN Money. The publications learned this from documents that Equifax recently submitted to the U.S. Senate’s Banking Committee.

In total, about 147.9 million Americans have been impacted by the data breach, the largest ever.

In public announcements issued in September and October, Equifax initially reported that 145.5 million U.S. consumers were “potentially” impacted by the breach. At the time, Equifax said the information that hackers accessed “primarily” included:

Names

Social Security numbers

Dates of birth

Addresses

Driver’s license numbers (“in some instances”)

Additionally, for small groups of U.S. consumers, the following information was accessed:

The WSJ and CNN reported that the following data on at least some consumers was also accessed:

Tax identification numbers

Email addresses

Driver’s license issue dates

Driver’s license states

How to protect yourself

When you’re worried about possible identity theft, the single strongest protection for your finances is a complete credit freeze. By “complete,” I mean freezing your credit with all three major nationwide credit reporting companies: Equifax, Experian and TransUnion.

A credit freeze, also known as a security freeze, blocks others from accessing your credit file. The U.S. Consumer Finance Protection Bureau explains:

“Creditors typically won’t offer you credit if they can’t access your credit reporting file, so a freeze prevents you or others from opening accounts in your name. Security freezes can be useful in preventing an identity thief from opening a new credit account in your name.”

Another option you may come across is a new “Lock & Alert” service that Equifax recently launched. Credit locks do not offer the same legal protections as credit freezes, though. We detailed further drawbacks of locks in “Why a Credit Freeze Beats Equifax’s Free ‘Credit Lock‘” after Equifax first announced its lock service.

Additionally, in recent weeks, the webpage for Equifax’s lock service has been up and down. For example, I got a “404 Not Found” error message when I tried to visit it several weeks ago.

Other folks have also reportedly experienced other technical issues with the site. They include Money Talks News founder Stacy Johnson, who tried to access the site last month. At the time, he said:

“I tried to register for the free Lock and Alert service from Equifax this morning. After filling in lots of info, the website said, ‘We can’t complete your request at this time. Please call the Customer Care team.'”

How to find out if you’re an identity theft victim

In addition to securing your finances, such as via a credit freeze, you also should request copies of your consumer reports to find out whether a cyberthief has used your personal information to open accounts in your name or to commit other crimes.

You’re hopefully familiar with one type of consumer report: credit reports. All consumers should check their credit reports regularly and anytime they suspect identity theft.

If someone has taken out a line of credit in your name — be it a credit card or some type of loan — it will show up on your credit reports. So, request your reports from the three major nationwide credit reporting companies and study them for activity you don’t recognize.